Packaging of liquids

ABSTRACT

THE INVENTION CONCERNS A METHOD FOR PACKAGING A LIQUID THE LIQUID IS FED PORTIONWISE THROUGH COOLING MEANS TO PROCE FROZEN SOLID ENTITIES WHICH ARE TRANSFERRED TO APPARATUS WHICH APPLIES A SUBSTANTIALLY EVEN LAYER OF COATING MATERIAL OVER THE SURFACE OF THE ENTITIES, THE COATING MATERIAL BBEING THEREAFTER INDUCED OR ALLOWED TO SOLIDIFY AND THE FROZEN CONTENTS TO MELT, WHEREBY SEALED CONTAINERS WITH LIQUID CONTENTS ARE PRODUCED.

United States Patent Horsewell et al.

154] PACKAGING OF LIQUIDS [72] Inventors: Henry George Horsewell; ArthurJohn Terry, both of Hampshire, En-

gland [73] Assignee: Brown. and Williamson Tobacco Corporation,Louisville, Ky.

22 Filed: 1 Mar-ch31, 1970 21 Appl. No.:22,354

[30] Foreign Application Priority Data- March 24, 1969 Great Britain..15318 [52'] US. Cl. .62/60, 53/25, 62/66, 99/138, 117/100 B, 264/28[51] Int. Cl. ..B65b 63/08 [58] Field of Search ..141/82; 117/100 B;264/28; 99/138; 53/25; 62/1, 66, 60, 75, 120, 123,

[56] References Cited UNITED STATES PATENTS 7 1,434,397 11/1922 Mock..264/28 X [151 3,693,369 [451 Sept. 26, 1972 2,800,456 7/1957 Shepherd..62/1 X 3,171,174 3/1965 Mellen, Jr. et al ..264/28 X 3,350,296 10/1967Torobin ..62/123 X Primary Examiner-Meyer Perlin AssistantExaminerRonald C. Capossela AttorneyKane, Dalsirner, Kane, Sullivan &Kurucz [5 7] ABSTRACT The invention concerns a method for packaging aliquidaThe liquid is fedportionwisethrough cooling meansto producefrozen solid entities which are transferred to apparatus which applies asubstantially even layer of coating material over the surface of theentities, the coating material being thereafter induced or allowed tosolidify and the frozen contents to melt,

whereby sealed containers with liquid contents are produced.

2 Claims, 6 Drawing Figures PAIENTED8P26 m2 7 3,693,369

SHEET 1 BF 4 INVENTORS HENRY GEORGE HOQSEWELL ARTHUR JOHN TERRY SHEET 2BF 4 PATENTED SEP 26 I512 INVENTORS HENRY GEORGE HOESEWELL. ARTHUR JOHNTERRY ATTORNEY5 7 BY 544D PATENTEDSms m2 SHEET 0F 4 FIGS.

In 2 illilltiawlil Flee.

- mvEmoRs HENRY GEORGE. HorzsEwEu. ARTHUR JOHN W'ERRYY m ,ag ATTORNEYS vPACKAGING F LIQUIDS A This invention concerns the packaging of liquids,

Sealed containers, such as glass ampoules or plasm tics sachets, whichprotect their contents against spillage and deterioration, can be usedfor aqueous.

liquids, but have the disadvantage that they may be difficult to open incircumstances where ready opening by digital pressure alone is required.Also, the material of such containers may be inherently unsuitable forsome purposes, for instance if they are required as components to beused in moistenable tobacco-smoke An object of the present invention isto provide a method whereby liquids can readily and easily be totallyenclosed in packages which are rupturable under digital pressure.

According to the invention, a liquid which is required to be packaged isfed portion-wise through cooling means, to produce frozen solidentities, possibly of substantially spherical shape, which, afterremoval from the cooling means, are transferred to apparatus whichapplies a layer of coating material substantially evenly overthe-surface of the solid entities, the coating material being thereafterinduced or allowed to solidify and the frozen contents to melt, wherebysealed containers with liquid contents are produced.

Preferably, the 'cooling means may comprise a cold liquid or mixture ofliquids through which the liquid to be packaged is passed and which issubstantially immiscible with, and of substantially lower freezing pointthan, the liquid to be packaged. Additionally, the cooling means shouldnot only be of viscosity such that undue turbulence is minimised in theportions of the liquid to be packaged, but also of greater density thanthis liquid. The combination of these two physical properties may beused to control the rate of movement of the portions through the coolingmeans.

Advantageously, the coating material is applied rotating in the samedirection above a bath of the coating material into which at least oneof the rollers dips, the frozen entities being supplied to the upperbight between the said rollers. One of these rollers may be helicallygrooved around its periphery, while the periphery of the other may beprovided with shallow grooves substantially parallel to the axis ofrotation. Portions of the material are picked up by the shallow groovesand deposited on the frozen entities in the aforesaid bight. The coatingmaterial may be a synthetic or natural wax, such for instance asparaffin wax, or a plastics material or a mixture thereof, which willform over the frozen liquid a continuous even coating which can behardened to form a rupturable or friable sealed container. It may beapplied as a solution, suspension or emulsion, or in molten form.

One manner of carrying the invention into effect upon a small-productionscale will now be more fully described by way of example, with referenceto the accompanying drawings, in which:

FIG. 1 is a diagrammatic illustration of an, apparatus for producingsmall balls of ice,

modification, and

FIG. 2 a perspective view of an apparatus for wax coating the saidballs,

FIG. 3 a plan view of a part of the latter apparatus,

FIG. 4 a part-section on the line IV-IV in FIG. 3,

FIG. 5 is a view similar to FIG. 3 illustrating a FIG. 6 a transversevertical section thereof.

The apparatus for producing ice balls shown in FIG. 1 comprises a columnor tower 1 formed by a thermally insulated vertical glass tube, 4 inchesin diameter and 8 feet high, filled with a mixture of1,1,1-trichloroethane (approx; and n-hexane (approx. 40%) having aspecific gravity of 1.09 at 25 C. The evaporator coil 2 of a coolingsystem comprising a condensing unit 3 is located on the inside of thewall of the column 1, where it is immersed in the mixture. Thecondensing unit operates with F mon- 22 and has a rating of 1 horsepower. The system maintains the temperature of the mixture in the column1 substantially constant at 25 C.

Water containing l /2% glycerine is injected in drops through a jet ornozzle 5 of 1.2 mm. dia. in the base of the column 1 under a head inexcess of the pressure of the mixture there. For this purpose, the wateris supplied from tank 6 mounted approximately 11 feet above the saidbase. A needle valve 7 regulates the flow of water into the column 1,the rate of flow being measured by a standard flow-meter 8. The jet 5 isscrewed, so as to be replaceable, into a block 9 which can be maintainedat a temperature of approximately 50C by means of a small electricalheating element 10, whereby the water is prevented from freezing in thejet. This heater can also be used for initially unfreezing water in thejet 5 after an inoperative period. A gate valve 11 is also incorporatedin the 7 block 9, so that the jet can be removed without draining thecolumn. Due to their lower specific gravity, the water drops leaving thejet 5 pass up through the mixture in the column 1 and become frozen intoice balls 12. These ice balls 12 pass into an overflow pipe 13 at thetop of the column 1 and are removed with the assistance of a secondcirculatory system. In this system, the mixture of solvents is cooled ina heat exchanger tank 14 to approximately -30 C. the cooling beingeffected by a second evaporator coil 15 supplied from the condensingunit 3. The cooled solvent mixture is drawn from the tank 14 by a pump16,

passed through a filter 17, to remove any frozen water particles, andinjected at 18 into the top of the column 1. The mixture flows throughthe overflow pipe 13, which is provided with a cock 19, into a smallheader 20 connected to the tank 14. The ice balls 12 from the column 1are carried through the pipe 13 with the solvent mixture, but areretained in a collecting pan 21 above the header 20. Periodically, theice balls are removed from the pan 21 and hardened off in a deep freezecabinet maintained at a temperature of about 2() C.

The diameter of the ice balls thus produced is consistent and, with aninternal jet diameter of 1.2 mm., is approximately 6.0 mm. Ice balls ofsmaller or larger diameter can be obtained by using a smaller or largerjet diameter, generally within a range of 1.0 to 1.5 mm.

When the ice balls have been hardened arr, theyare transferred to theapparatus illustrated in FIGS. 2 to 4, in which they are coated withwax. The coating apparatus comprises a roller 22, 4 inches in diameterand 3 inches wide, which has shallow axial grooves and dips into aheated bath 23 of hot molten wax and a second roller 24, 3 inches indiameter and 3 inches wide, which has a helical groove of semi-circularcross-section capable of accommodating the ice balls. Suitably thehelical groove has a diameter of about 8 mm. and comprises four or morefull turns in the roller 24. The two parallel horizontal rollers 22, 24are driven in the same direction (clockwise in FIG. 2) by electricmotors 25, 26 whose speeds (up to 200 r.p.m.) are separatelycontrollable by controllers 27, 28. The rollers may alternatively bedriven from a single motor through a gearbox.

The ice balls are placed in a lagged refrigerated hopper 29 which hasstirring means (not seen) driven by a motor 30. From the hopper 29, theice balls pass down a feed tube 31 from the lower end of which they arefed singly and intermittently to a point above the bight between therollers 22, 24 by a slidable dispenser rod 32 which is moved in theoperative direction by a cam 33 on a disc 34 driven in synchronism withthe roller 24 by the motor 26 and is returned by a restoring spring 35.A baffle plate 36 (not shown in FIG. 2)

ensures that each ice ball falls into the starting point.

of the helical groove. It is then carried by the latter, in the bightbetween the rollers, across the face of the roller 22, whose groovesserve not only to carry wax and deposit it on the surface of the iceball, but also to cause the ice ball to rotate and thus to become wellocated with the wax all over its surface.

- of holes 40. The balls fall in turn into the holes 40 but apreventedffifiipassing atonce throughfhe holes by a fixed plate 41. Theyfall from the disc 39 into the helical groove of the roller 24 at thepoint 42, where the plate is cut away.

When an ice ball 12 thus coated has progressed to the outer end of thehelical groove it falls over a lip 36' or down a guide into a shallowtrough 37, through which cold water from inlets 38 is flowing. Asillusfated, there ma be a second such t r5u gh 39 to which he ice bansfalldown a chute 40. Finally the ice balls pass down a further chute4l'for collection and storage,

the water being carried away by a drain 42. By this' stage, the waxcoating has solidified and hardened, so that it is immaterial if the iceballs have already reverted to the liquid state.

With the above-described apparatus, spherical wax capsules of consistentsize can be obtained at a rate of 120 per minute with the rollers 22, 24rotating at 120 r.p.m. The coating material used is a mixture consistingof 25% of a wax-resin known by the trade name Surfowax 220H (produced byCampbell Technical Waxes Limited) and or normal paraffin wax having amelting point of 65 to 68 C.

As an alternative for the solvent mixture referred to above, use may bemade of other homogeneous mixtures of solvents, such as carbontetrachloride and petroleum ether, having a specific gravity within therange of 1.02-1.20 at room temperature, these mixtures being maintainedat a substantially constant temperature which is below the melting pointof the liquid to be encapsulated. In place of the heatexchanger l4, 15,the solvent mixture may be circulated through a cooling coil which mayitself be cooled by solid carbon dioxide. The frozen liquid balls may beseparated from the solvent mixture by a filtering screen preceeding thecooling element of the circuit for that mixture.

The invention can be employed for the encapsulation of liquids otherthan water, for example solutions of salts and other substances, and forthe production of capsules serving a variety of purposes, for examplesmoke-filtration, smoke-flavour improvement and the like.

We claim:

1. A method for encapsulating a liquid composition comprising:

(a) feeding said liquid portion-wise into a cooling means adapted toform solid entities of said liquid to be encapsulated, said coolingmeans including a cold liquid which is substantially immiscible with andof substantially lower melting point and of greater density than theliquid to be encapsulated;

(b) passing said portion-wise liquid upwardly through the cooling liquidto form solid entities; and

(c) coating the surfaces of the solid entities with a layer of materialwhich when hardened forms an encapsulated rupturable container.

2. The method of claim 1 wherein said layer of coating material isapplied to the solid entities by transferring the solid entities from acooling liquid to a coating station then simultaneously applying a filmof coating material from opposite sides while conveying the solid engties from the coating station.

